Question

arccos(-1)+arcsin(-1/2)

Answer 1

$\arccos(-1)+\arcsin(- \frac{1}{2})=\pi- \frac{ \pi}{6} =\frac{5 \pi}{6}$

Answer 2

$arccos(-1)= \pi$
$arcsin(- \frac{1}{2}=- \frac{ \pi }{6}$
$arccos(-1)+arcsin(- \frac{1}{2})= \pi - \frac{ \pi }{6} = \frac{5 \pi }{6}$